SEER Inquiry System - View
Source 1: 2007 MP/H Rules
MP/H Rules/Multiple primaries--Breast: Please tell me if this is one or two breast primaries. See discussion.
Patient has 2 tumors in the left breast -- one at 2:00 and one at 3:00. The final diagnosis from the left mastectomy is: multifocal (2 foci) invasive ductal carcinoma (mpT1c N0 see template) with associated intermediate grade ductal carcinoma in situ located between the invasive foci.
Larger 2:00 focus: moderately diff ductal carcinoma with mucinous differentiation (1.4cm.)
Smaller 3:00 focus: Moderately to poorly diff ductal carcinoma (1.2 cm.)
I would code the 2:00 tumor as 8523/3 and the 3:00 tumor as 8500/3. I do not know whether to invoke rule M11 (since 8523 is not in Tables 1 or 2) or rule M12. M11 would make this a single primary; M12 makes this 2 primaries.